With the development of mobile communications systems, the quality of service that can be provided by a system is increasingly higher. In order to maintain the long-term competitive edge of 3GPP, LTE-A (LTE-Advanced, a further evolution of LTE) standards are being set. In order to improve the spectral efficiency of the system and the throughput of a user equipment (User Equipment, UE), carrier aggregation (CA, Carrier Aggregation) is introduced to the LTE-A. The carrier aggregation refers to that the UE can use multiple component carriers (CC, Component Carrier) at the same time to perform uplink and downlink communications, so as to support high-speed data transmission.
The Release-10 version of the 3GPP supports cell (cell) aggregation (or carrier aggregation) in a base station, and adopts an underlying aggregation solution, that is, data of a service or a radio bearer (Radio Bearer, RB) may be delivered in multiple cells of the base station. Specifically, a scheduling program of the base station decides in real time in which cell a packet of data of a service is delivered, for example, a previous packet of data is delivered in one cell, and a next packet of data may be delivered in another cell.
However, the foregoing version does not yet support cell aggregation between base stations; as a result, the throughput of a user equipment cannot be further increased.